The methods used today, and since the advent of dialysis some 50 years ago, in relation to kidney failure all relies on methods using semipermeable membranes.
While for example blood dialysis may eliminate waste products from blood, they may at the same time, unfortunately, eliminate vital to health, non-waste substances from blood. Examples of substances that should not be eliminated are albumin and some immunoglobulins.
There are many toxic substances that are poorly removed by current dialysis methods. These substances may cause uremic conditions in patients with renal failure causing suffering and illness for these patients.
As an example, the following substances are poorly removed by most known dialysis techniques: p-cresol; homocysteine; AGE (advanced glycation end products), and hippouric acid. These toxins are at least partly protein-bound making their removal difficult with conventional dialysis procedures.
Other toxic substances found in the biological system of a renal failure patient are even un-known and are still to be identified. The EUTox (European Uremic Toxin Work Group) has found that middle molecular weight substances may be strongly toxic and may be responsible for uremic conditions. Middle molecular weight substances are normally poorly removed by conventional blood dialysis.
EUTox has so far assembled the following list of middle molecular weight substances: Adrenomerullin; Atrial natriuretic peptide; β2-microglobulin; β-endorphin; cholecystokinin; clara cell protein; complement factor D; cystatin C; degranulation inhibitor protein; delta sleep-inducing peptide; endothelin; hyaluronic acid; interleukin-1α; interleukin-6; κ-1 g light chain; λ-1 g light chain; leptin; methionine-enkephaline; neuropeptide Y; parathyroid hormone; retinol-binding protein; tumor necrosis factor-α, etc.
A further problem with conventional, membrane-based dialysis is that albumin and other proteins may adhere to the surface of the membrane, which results in blocking of the pores of the membrane, resulting in an impaired dialysis process. In addition, albumin is lost, which should be prevented, since dialysis patients in general have low concentration of albumin in blood.
Many of these problems can be attributed to the use of a membrane, which is responsive for the selection of substances to be separated from the body fluid. Thus, there is a need in the art for a method and a device, which is at least partly not based on the use of membranes.